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10844 Uppsatser om Electric power system - Sida 11 av 723

EU som global politisk aktör - En utvärdering av Normative power Europe

What kind of international actor is the European Union and how shall we define it? These are questions that many have tried to answer often by addressing the apparent uniqueness of the EU itself. One of these theories is Normative power Europe. A theory whose main argument is that the EU is best perceived as a changer of norms. My aim with this thesis is to test this claim and to see if the Union should be regarded as a normative power.

Testplattform för nätverks-RTK i syfte att ge en rikstäckande GPS-tjänst med centimeternoggrannhet

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Simulering av vindkraftverk och närliggande elnät vid Risholmen i Göteborg i SimPowerSystems

With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.

Trafiken till Göteborgs södra skärgård - En annorlunda kollektivtrafik

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Vägar och markanspråk inom vindkraftsparker i Västerbottens län : Hur verkliga mått förhåller sig till vad som uppges i miljökonsekvensbeskrivningar

The purpose of this study was to increase the level of knowledge in the field of Environmental Impact Assessment (EIA) for wind power. The study includes six wind power farms in the County of Västerbotten in northern Sweden. The main questions were: What are the real dimensions of roadways and land claims for both roads and wind power turbines? How do those dimensions correlate with the dimensions stated in the EIA? Are there any differences in values of the dimensions between the wind power farms that are included in this study? The width of the roadways and the land claims for both roads and wind turbines in wind power farms were examined on site. The results from the examinations were compared with the dimensions available in the EIA for each wind power farm.

Transformatordiagnostik genom dissolverad gasanalys

The transformer is one of the most common and most important electric machines for power companies. Cost of investment and the economic worth of a transformer are counted in millions of SEK. Because of that, proper maintenance actions that may lead to longer technical life time should be the aim in all situations.The aim with the report was to perform transformer diagnosis by dissolved gas analysis on Umeå Energi AB´s power transformers and a risk assessment. The report should also contribute to longer life time for the transformers.Oil samples were taken from each transformer two times. The first sample in summer 2013 and the second in April 2014.

Rostfritt stål som ett alternativt material till koppar i tappvattenledningar för bostäder

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Ska pyramiderna rivas?: en studie om mikromakt

It has been demonstrated in this study how people working in frontline jobs in service organizations are exercising ?micro power?. The use of ?micro power? is defined as ?to in ones professional role, without objectively defensible reasons, impose sanctions on a customer?. The interviewees are explaining their use of ?micro power? with mood, working conditions, and customers? behavior.

Det talas om utbrändhet : vilken roll spelar maktstrukturen

In this paper we investigate whether power structures in organizations have an influence in the process that leads to burnout. We analyze if these power structures affect the individual?s health condition toward burnout in a way that leads to disability and subsequent absence from work. In the study, six persons who all have been unable to work due to burnout have been studied through qualitative, semi-structured interviews. The material have been coded with three different themes; leadership and hierarchy, responsibility and delegation of responsibility and performance and loyalty.

Optimering av ett småskaligtvattenkraftsystem

This master thesis covers the seasonal planning of a small scale hydropower system. The system in this study is owned and operated by Mälarenergi Vattenkraft AB. The total system consists of 4 different main rivers with 24 hydropower stations and several dams. The total installed power in the system is 43.75 MW. Most of the hydropower stations are regarded as small scale hydropower stations and thus entitled to green certificates.In this report the issue of planning is formulated as an optimization problem.

Analys av designalternativ för snabbare dynamik i kolkraftverk med koldioxidavskiljning

Combustion of fossil fuels is today the dominating source of energy. During combustion,carbon dioxide is formed. The carbon dioxide accumulates in the atmosphere,which raises the global average temperature on earth through the so called greenhouseeffect. The only way to reduce the emissions of carbon dioxide from combustionin a coal fired power plant is through carbon capture and storage (CCS).Post-combustion capture is a technology to separate carbon dioxide from the uegas after the combustion for efficient transport and storage. The steady state operationof coal fired power plants with post combustion capture has already beenthoroughly investigated on a pilot scale, however much work remains to investigatethe plants dynamic operation.

Vetenskap och makt. En analys av två vetenskapliga paradigms skilda maktlogiker.

This essay analyse the relationships between scientific paradigms and different logics of power in the field of psychiatry, primarily in the fields of attention disorders of children and schizophrenia. In these two fields of psychiatric research and treatment, there exist two scientific paradigms, a biological/neuropsychiatric and a socialpsychological, working from different standpoints regarding questions of ontology, epistemology and theories of value. Drawing from Thomas Kuhns paradigmatic theory of science, and Michel Foucaults concept of power, this essay proposes that different paradigmatic standpoints gives rise to different logics of power. Relying on the concept of power/knowledge and different paradigmatic standpoints, the essay states that the biological/neuropsychiatric paradigm produces a biological individualising logic of power that fixes the individual to his/hers biological condition. This in contrast to the socialpsychological paradigm, which on the basis of its paradigmatic standpoints produces a social-group related logic of power.

Implementering av en PSS i Trängslets kraftstation

The purpose of this master thesis is to implement and validate a Power System Stabilizer (PSS) to a generator at Trängslet hydropower station in Dalarna, Sweden. Problems with local rotor oscillations can occur at the hydropower station when power is transferred on a new power line (130 kV) from Northern to Southern part of Dalarna. To ensure good operation properties on this power line Fortum Generation AB and Fortum Distribution AB wants to activate a PSS on a generator.There have been investigations in which situations and what equipment that contributes to rotor oscillations. When this is known the PSS is tuned to damp these oscillations by choosing a good set of parameters. The most important parameters for good performance are to choose amount of gain and phase compensation.

Ny teknik för småskalig kraftvärme : - med fokus på Organisk RankineCykel (ORC)

As a part of the fight against the global warming the energy production needs to be more efficient and redirected towards sustainable options. One alternative is cogeneration, which means that electricity and heat is produced in one plant. The purpose with this survey is to examine if there are any commercial available combined heat and power techniques, based on combustion of solid moist biomass, which are suitable to small-scale applications. The technique must be able to produce between 2 and 10 MW thermal and the heat demand is a Swedish district-heating system. When already published reports had been studied, the Organic Rankine Cycle (ORC) was chosen as the most suitable technique.

Alternativ uppvärmning av reningsverket på Utö - En studie av energibesparingsmöjligheterna i syfte att minska uppvärmningskostnaderna

The projects objective is to find an alternative method of heating (the current method being via electric heating) the sewage treatment plant on the island Utö in Stockholm?s archipelago in order to reduce the energy consumption and ultimately the cost for heating the plant. The project is given by ?Skärgårdsstiftelsen? (The Archipelago Foundation) and is a part of the larger EU-project ?Green Islands?.A model for the plants total heating demand is established in order to get a good perception of how much money can be saved using alternative heating methods. The heating demand model gives an annual heating demand of approximately 32 500 kWh and a maximum heating power demand of around 24,7 kW.

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